U.S. patent application number 15/197304 was filed with the patent office on 2017-01-05 for retrieval devices and related methods of use.
This patent application is currently assigned to Boston Scientific Scimed, Inc.. The applicant listed for this patent is Boston Scientific Scimed, Inc.. Invention is credited to Michael S.H. Chu.
Application Number | 20170000506 15/197304 |
Document ID | / |
Family ID | 56409716 |
Filed Date | 2017-01-05 |
United States Patent
Application |
20170000506 |
Kind Code |
A1 |
Chu; Michael S.H. |
January 5, 2017 |
RETRIEVAL DEVICES AND RELATED METHODS OF USE
Abstract
A retrieval device may have a contracted state and an expanded
state. The retrieval device may include a sheath and at least three
support members. Each of the support members may have a first
portion with a first cross-sectional shape and a second portion
with a second cross-sectional shape different from the first
cross-sectional shape. A proximal end fixed of each of the support
members may be coupled to the sheath, and a distal end may be
movable relative to the sheath. The retrieval device may further
include at least three movable members movable relative to the
support members. Each movable member may extend through a lumen of
one support member of the at least three support members and
through a lumen of a different support member of the at least three
support members.
Inventors: |
Chu; Michael S.H.;
(Brookline, MA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Boston Scientific Scimed, Inc. |
Maple Grove |
MN |
US |
|
|
Assignee: |
Boston Scientific Scimed,
Inc.
Maple Grove
MN
|
Family ID: |
56409716 |
Appl. No.: |
15/197304 |
Filed: |
June 29, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62186718 |
Jun 30, 2015 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61B 17/221 20130101;
A61B 2017/2212 20130101; A61B 2017/0042 20130101; A61B 2017/2215
20130101; A61B 2017/00862 20130101; A61B 2017/22035 20130101 |
International
Class: |
A61B 17/221 20060101
A61B017/221 |
Claims
1. A retrieval device having a contracted state and an expanded
state, comprising: a sheath; at least three support members each
having a first portion with a first cross-sectional shape and a
second portion with a second cross-sectional shape different from
the first cross-sectional shape, a proximal end fixed to the
sheath, and a distal end movable relative to the sheath; and at
least three movable members movable relative to the support
members, each movable member extending through a lumen of one
support member of the at least three support members and through a
lumen of a different support member of the at least three support
members.
2. The retrieval device of claim 1, wherein the first
cross-sectional shape is circular and the second cross-sectional
shape is ovular.
3. The retrieval device of claim 1, wherein the first portion is
positioned adjacent the distal end and the second portion is
positioned adjacent the proximal end.
4. The retrieval device of claim 1, wherein the second portion is
positioned along the support member between two separate and
distinct first portions.
5. The retrieval device of claim 1, wherein the lumen of each
support member along the second portion is sized so as to prevent
the movable members received therethrough from rotating about one
another.
6. The retrieval device of claim 1, wherein each support member is
comprised of polyimide, PET, or combinations thereof.
7. The retrieval device of claim 1, further including a transition
portion between the first portion and the second portion of each of
the support members.
8. The retrieval device of claim 1, wherein each of the at least
three movable members are configured to slide distally within one
or more of the at least three support members during transition of
the retrieval device from the contracted state to the expanded
state.
9. The retrieval device of claim 1, wherein each support member is
parallel to a longitudinal axis of the sheath while the retrieval
device is in the contracted state.
10. The retrieval device of claim 1, wherein each support member is
configured to bow radially outward from a longitudinal axis of the
sheath in the expanded state.
11. The retrieval device of claim 1, wherein the sheath encompasses
at least a portion of the movable members and at least a portion of
the support members.
12. The retrieval device of claim 1, further including a stop
located at an end of at least one movable member to restrict
movement of the end after moving a distance distally.
13. The retrieval device of claim 12, wherein the stop includes a
coupling securing ends of the at least three movable members
together.
14. The retrieval device of claim 1, wherein each of the at least
three movable members includes a U-shaped bend located distally of
the distal ends of the at least three support members.
15. The retrieval device of claim 14, wherein the U-shaped bend is
preformed and urges the support members toward the contracted
state.
16. A retrieval device, comprising: a sheath; at least three
support members each tapering from a first portion with a circular
cross-sectional shape to a second portion with a ovular
cross-sectional shape, wherein each of the support members is
movable between a contracted configuration extending along a
longitudinal axis of the sheath in the contracted configuration,
and an expanded configuration bowing radially outward from the
longitudinal axis of the sheath; and at least three movable
members, each movable member forming a bridge between two different
support members of the at least three support members.
17. The retrieval device of claim 16, wherein the first portion is
positioned adjacent a distal end of the support members and the
second portion is positioned adjacent a proximal end of the support
members.
18. The retrieval device of claim 16, wherein the retrieval device
includes three bridges formed by the at least three movable
members, wherein the three bridges form a distally-facing loop when
the support members are in the expanded configuration.
19. The retrieval device of claim 16, wherein each bridge forms a
side loop with the two different support members that the bridge is
between.
20. A method for retrieving an object using a retrieval device
including a sheath, at least three support members each having a
varied cross-sectional shape along a length of the support members,
a proximal end fixed to the sheath, and a distal end movable
relative to the sheath, and at least three movable members movable
relative to the support members, each movable member extending
through a lumen of one support member of the at least three support
members and through a lumen of a different support member of the at
least three support members, the method comprising: moving the
movable members distally to transition the retrieval device from a
contracted state to an expanded state.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This patent application claims the benefit of priority under
35 U.S.C. .sctn.119 to U.S. Provisional Patent Application No.
62/186,718, filed Jun. 30, 2015, which is herein incorporated by
reference in its entirety.
TECHNICAL FIELD
[0002] Various examples of the present disclosure relate generally
to retrieval devices and related systems and methods. More
specifically, the present disclosure relates to devices, systems,
and methods for retrieving objects within a patient.
BACKGROUND
[0003] Retrieval devices are often used to remove organic material
(e.g., blood clots, tissue, and biological concretions such as
urinary, biliary, and pancreatic stones) and inorganic material
(e.g., components of a medical device or other foreign matter),
which may obstruct or otherwise be present within a patient's body
cavities or passages. For example, concretions can develop in
certain parts of the body, such as in the kidneys, pancreas,
ureter, and gallbladder. Minimally invasive medical procedures are
used to remove these concretions through natural orifices, or
through an incision, such as during a percutaneous nephrolithotomy
("PNCL") procedure. Further, lithotripsy and ureteroscopy, for
example, are used to treat urinary calculi (e.g., kidney stones) in
the ureter of a patient.
[0004] Retrieval devices may include end effectors for manipulating
objects. An exemplary end effector may have a plurality of arms
that support a front loop that forms when the end effector is
opened. The size of the front loop may limit the size of an object
that can be captured, repositioned, and/or released from the end
effector. For some procedures, there may be a need to increase the
size of a front loop of an end effector to facilitate the
capturing, repositioning, and/or releasing of larger objects. It
may also be desirable to have an end effector close back down to a
low-profile state to facilitate insertion and withdrawal of the end
effector into and from a target area, and/or to capture,
reposition, and/or release smaller objects. Further, during a
procedure, one or more portions of the front loop may entangle with
one another thereby distorting the end effector and potentially
reducing its effectiveness and life span. Thus, there remains a
need for retrieval devices with improved capabilities.
[0005] Further, known medical retrieval devices are complex,
requiring many components and/or labor-intensive manufacturing
processes. The assembly of small parts often requires visual
magnification and specialized training. The available joining
mechanisms can increase the profile of the medical retrieval
devices beyond optimal design parameters, and may be the weakest
structural points. These drawbacks can result in medical retrieval
devices that are bulky, expensive, and prone to failure.
[0006] The systems and methods of the current disclosure may
address some of the deficiencies described above and/or other
problems in the art.
SUMMARY
[0007] In one example, a retrieval device may have a contracted
state and an expanded state. The retrieval device may include a
sheath and at least three support members. Each of the support
members may have a first portion with a first cross-sectional shape
and a second portion with a second cross-sectional shape different
from the first cross-sectional shape. A proximal end fixed of each
of the support members may be coupled to the sheath, and a distal
end may be movable relative to the sheath. The retrieval device may
further include at least three movable members movable relative to
the support members. Each movable member may extend through a lumen
of one support member of the at least three support members and
through a lumen of a different support member of the at least three
support members.
[0008] The retrieval device may additionally or alternatively
include one or more of the following features: the cross-sectional
shape of the first portion may be circular and the cross-sectional
shape of the second portion may be ovular, the first portion may be
positioned adjacent the distal end and the second portion may be
positioned adjacent the proximal end; the second portion may be
positioned along the support member between two separate and
distinct first portions; the lumen of each support member along the
second portion may be sized so as to prevent the movable members
received therethrough from rotating about one another; each support
member may be comprised of polyimide, PET, or combinations thereof.
a transition portion between the first portion and the second
portion of each of the support members; each of the at least three
movable members may be configured to slide distally within one or
more of the at least three support members during transition of the
retrieval device from the contracted state to the expanded state;
each support member may be parallel to a longitudinal axis of the
sheath while the retrieval device is in the contracted state; each
support member may be configured to bow radially outward from a
longitudinal axis of the sheath in the expanded state; the sheath
may encompass at least a portion of the movable members and at
least a portion of the support members; a stop located at an end of
at least one movable member to restrict movement of the end after
moving a distance distally; the stop may include a coupling
securing ends of the at least three movable members together; each
of the at least three movable members may include a U-shaped bend
located distally of the distal ends of the at least three support
members; and the U-shaped bend may be preformed and urge the
support members toward the contracted state.
[0009] In another example, a retrieval device may include a sheath
and at least three support members. Each of the support members may
taper from a first portion with a circular cross-sectional shape to
a second portion with a ovular cross-sectional shape. Additionally,
each of the support members may be movable between a contracted
configuration extending along a longitudinal axis of the sheath in
the contracted configuration, and an expanded configuration bowing
radially outward from the longitudinal axis of the sheath. The
retrieval device may further include at least three movable
members. Each movable member may form a bridge between two
different support members of the at least support members.
[0010] The retrieval device may additionally or alternatively
include one or more of the following features: the first portion
may be positioned adjacent a distal end of the support members and
the second portion may positioned adjacent a proximal end of the
support members; the retrieval device may include three bridges
formed by the at least three movable members, wherein the three
bridges may form a distally-facing loop when the support members
are in the expanded configuration; and each bridge may form a side
loop with the two support members that the bridge is between.
[0011] In another example, a method for retrieving an object using
a retrieval device is disclosed. The retrieval device may include a
sheath and at least three support members. Each of the at least
three support members may have a varied cross-sectional shape along
a length of the support members, a proximal end fixed to the
sheath, a distal end movable relative to the sheath, and at least
three movable members movable relative to the support members. Each
movable member may extend through a lumen of one support member of
the at least three support members and through a lumen of a
different support member of the at least three support members. The
method may include moving the movable members distally to
transition the retrieval device from a contracted state to an
expanded state.
[0012] It is understood that both the foregoing general description
and the following detailed description are exemplary and
explanatory only and are not restrictive of the disclosure, as
claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The accompanying drawings, which are incorporated in and
constitute a part of this specification, illustrate examples of the
present disclosure and together with the description, serve to
explain the principles of the disclosure.
[0014] FIG. 1 is a full view of a retrieval device in an extended
and expanded state.
[0015] FIG. 2 is a perspective view of a distal end of the
retrieval device of FIG. 1.
[0016] FIG. 3 is a perspective view of the distal end of the
retrieval device of FIG. 1 in a retracted state, in accordance with
examples of the present disclosure.
[0017] FIG. 4 is a distal end view of the retrieval device of FIG.
1, in accordance with examples of the present disclosure.
[0018] FIG. 5 is a cross-sectional view of the retrieval device of
FIG. 3 along line 5-5, in accordance with examples of the present
disclosure.
[0019] FIG. 6 is a side and partial view of the retrieval device of
FIG. 1, including an end effector in a retracted and contracted
state, in accordance with examples of the present disclosure.
[0020] FIG. 7 is a perspective view of a support member of the
retrieval device of FIG. 1.
[0021] FIG. 8 is a perspective view of a support member of a
retrieval device, in accordance with another example of the present
disclosure.
DETAILED DESCRIPTION
[0022] The present disclosure is drawn to retrieval devices and
related systems and methods. Reference will now be made in detail
to examples of the present disclosure, examples of which are
illustrated in the accompanying drawings. Wherever possible, the
same reference numbers will be used throughout the drawings to
refer to the same or like parts. The term "distal" refers to a
location farther away from a user when introducing a device into a
patient. By contrast, the term "proximal" refers to a location
closer to the user when placing the device into the patient.
Examples
[0023] FIG. 1 shows a full retrieval device 10, and FIGS. 2-6 show
various portions of the retrieval device 10. Referring to FIG. 1,
the retrieval device 10 may include a basket portion or grasper
portion 52 including a plurality of movable members 18, 20, and 22,
and a plurality of support members 26, 28, and 30. A proximal end
66, 68, and 70 of the support members 26, 28, and 30, respectively
may be coupled to an outer sheath 12 and a handle assembly 90 while
distal ends 76, 78, and 80 extend distally thereof. The handle
assembly 90 may be disposed at a proximal end 86 of the retrieval
device 10. The movable members 18, 20, and 22 may be coupled to the
handle assembly 90 and extend through the support members 26, 28,
and 30 and the outer sheath 12. As explained in more detail below,
movement of an actuator 92 of the handle assembly 90 may cause
relative movement between the movable members 18, 20, and 22, and
the support members 26, 28, and 30 so as to transition the grasper
portion 52 between an expanded state (FIGS. 1 and 2) and a
contracted state (FIGS. 3-6).
[0024] Referring to FIGS. 3-6, the outer sheath 12 of retrieval
device 10 may include a lumen 14 extending longitudinally
therethrough. The outer sheath 12 may be, for example, a hollow
tube of about 1.7-1.9 French, although the dimensions may differ
based on the type of procedure being performed with the retrieval
device 10. In another example, the outer sheath 12 may be a hollow
tube of about 1.7 to 1.9 French. As used herein, the terms "about,"
"substantially," and "approximately," indicates a range of values
within +/-5% of the stated value. The outer sheath 12 may be made
of a polymer material or combination of materials. A proximal
portion of the outer sheath 12 may be made of a different material
than a distal portion of the outer sheath 12. For example, the
distal portion of the outer sheath 12 may be made of a material
that is more flexible than the material of the proximal portion of
the outer sheath 12.
[0025] The retrieval device 10 may also include a drive member or
shaft 16. The drive member 16 may extend through the lumen 14 of
the outer sheath 12. The drive member 16 may be elongated, and may
include, for example, a wire, braid, cable, shaft, and/or any other
suitable drive member configured to receive or transfer
compression, tension, and/or torsional forces. The drive member 16
may have any suitable cross-sectional shape, including cylindrical,
elliptical, polygonal, and/or irregular. The drive member 16 may be
made of metals, polymers, or a combination of materials. It is also
contemplated that the drive member 16 may have a diameter of
approximately 0.0125 inches (0.03175 centimeters). The drive member
16 may have other diameters, however, depending on the type of
procedure being performed with the retrieval device 10.
[0026] The movable members of retrieval device 10 may include a
first movable member 18, a second movable member 20, and a third
movable member 22. The first movable member 18 may include a first
leg 18a, a reverse or U-shaped bend 18b, and a second leg 18c.
Similarly, the second movable member 20 may include a first leg
20a, a reverse or U-shaped bend 20b, and a second leg 20c. The
third movable member 22 may also include a first leg 22a, a reverse
or U-shaped bend 22b, and a second leg 22c. While three movable
members 18, 20, and 22 are shown, one or more additional movable
members may also be included. The bends 18b, 20b, and 22b may be
disposed between respective first and second legs 18a and 18c, 20a
and 20c, and 22a and 22c, respectively.
[0027] Each of the movable members 18, 20, and 22 may be formed of
any suitable material including, but not limited to, metals,
polymers, or a combination of materials. For example, one or more
of the movable members 18, 20, and 22 may be formed of a shape
memory material, such as Nitinol, and may be treated so as to
include an internal bias causing one or more of the movable members
18, 20, and 22 to move to a preselected position in the absence of
an urging force. For example, the U-shaped bends 18b, 20b, 22b of
the movable members 18, 20, and 22 may be preformed such as by heat
setting into the U-shaped bend shape. This preformed U-shaped bend
18b, 20b, 22b may facilitate a clamping of the distal ends of the
support members together in the contracted state (FIGS. 3-6). One
or more of the movable members 18, 20, and 22 may be a wire, braid,
cable, or shaft having any suitable diameter, such as a diameter of
about 0.003 inches (0.00762 centimeters), although other suitable
diameters may alternatively be utilized.
[0028] Each of the movable members 18, 20, and 22 may have any
suitable cross-sectional shape, including cylindrical, elliptical,
polygonal, and/or irregular. One or more of the movable members 18,
20, and 22 may include a portion flattened, machined, extruded,
drawn, and/or etched into a different profile than a remaining
portion. One or more of the movable members 18, 20, and 22 may be
slotted to allow deflection or directional bending. The exterior
surfaces of one or more of the movable members 18, 20, and 22 may
be roughened, notched, slotted, etched, sand-blasted, or otherwise
modified to provide a better gripping surface.
[0029] The movable members 18, 20, and 22 may be attached to the
drive member 16 at a first end. For example, proximal ends of the
first legs 18a, 20a, and 22a may be attached to the distal end of
the drive member 16. The attachment may be provided by one or more
of a splice joint, adhesives, melting, welding, crimping, and/or
any other suitable attachment mechanism. It is also contemplated
that a sleeve 24 may be placed over the proximal portions of the
first legs 18a, 20a, and 22a, and the distal portion of the drive
member 16 to secure the elements together. The sleeve 24 may be
made of a polytetrafluoroethylene like TEFLON. The sleeve 24 may be
heat shrinkable onto the first legs 18a, 20a, and 22a, and the
drive member 16. The sleeve 24 may have a length of about 11.5
centimeters, but it should be understood that the length and other
sleeve dimensions may vary based on the type of procedure being
performed with the retrieval device 10. The sleeve 24 may help
gather the first legs 18a, 20a, and 22a, to avoid radially outward
movement of the legs when pushed distally by the drive member 16,
giving the gathered portions added strength. The proximal portions
of each of the first legs 18a, 20a, and 22a may contact the
proximal portions of the other first legs. Longitudinal axes of the
proximal portions of the first legs 18a, 20a, and 22a may be
substantially parallel.
[0030] The support members of the retrieval device 10 may include a
first support member 26, a second support member 28, and a third
support member 30. Each of the support members 26, 28, and 30 may
have a varied cross-sectional size and/or shape. That is, for
example, one or more portions of the support members 26, 28, and 30
may be flattened. For example, as shown in FIG. 3, a first portion
26a of the first support member 26 may have a circular
cross-sectional shape, while a second portion 26b of the first
support member 26 may have an ovular, figure-8, and/or flattened
cross-sectional shape. Similarly, a first portion 28a of the second
support member 28 may have a circular cross-sectional shape, while
a second portion 28b of the second support member 28 may have an
ovular, figure-8, and/or flattened cross-sectional shape. Further,
a first portion 30a (FIG. 2) of the third support member 30 may
have a circular cross-sectional shape, while a second portion 30b
of the third support member 30 may have an ovular, figure-8, and/or
flattened cross-sectional shape. A transition or taper portion 26c,
28c, and 30c may be positioned between respective first and second
portions 26a, 26b, 28a, 28b, 30a, and 30b as shown in FIG. 3.
Alternatively, the cross-sectional shape of each of the first and
second portions 26a, 26b, 28a, 28b, 30a, and 30b may be circular,
and each of the first portions 26a, 28a, and 30a may be larger than
a respective second portion 26b, 28b, and 30b, as will be discussed
in further detail below. As shown in FIGS. 2, 3, and 6, a part of
each of the second portions 26b, 28b, and 30b are configured to be
received within outer sheath 12, while first portions 26a, 28a, and
30a extend distally of the second portions 26b, 28b, and 30b.
[0031] Each of the support members 26, 28, and 30 may be comprised
of any appropriate material, such as, for example, polyimide, PET,
and combinations thereof. An inner diameter of each of the first
portions 26a, 28a, and 30a, of each of the support members 26, 28,
and 30, may be about 0.0065 inches (0.1651 mm) and include a wall
thickness of about 0.0015 inches (0.0381 mm). Further, upon
flattening, each of the second portions 26b, 28b, and 30b of each
of the support members 26, 28, and 30 may be sized to tightly
(e.g., snugly, closely, etc.) receive a portion of at least two
moveable members 18, 20, and 22, each having a diameter of about
0.0031 inches (0.0787 mm) or less, therein and may be about 0.75
inches (19 mm) in length. As such, the at least two moveable
members 18, 20, and/or 22 may have a reduced number of degrees of
freedom in the second portions 26b, 28b, and 30b. For example,
second portion 26b of support member 26 may be configured to
receive a portion of moveable members 18 and 22, as shown in FIG.
4. Accordingly, the portion of moveable member 18 received within
second portion 26b of support member 26 may be limited to axial
movement along, or rotational movement about a central longitudinal
axis (not shown) of moveable member 18. Additionally, the portion
of moveable member 22 received within second portion 26b of support
member 26 may be limited to axial movement along, or rotational
movement about a central longitudinal axis of moveable member 22.
That is, due to the flattening of the second portion 26b of support
member 26, the portions of the moveable members 18 and 22 received
within the second portion 26b may be prevented from twisting about
and/or rotating about one another.
[0032] Flattening of the second portions 26b, 28b, and 30b may be
done through any appropriate means such as, for example,
compressing, rolling, heat reflowing, extruding, joining and/or
combinations thereof. For example, each of the second portions 26b,
28b, and 30b, of each of the support members 26, 28, and 30, may be
compressed against a mandrel individually and/or simultaneously so
as to alter the cross sectional shape of the second portions 26b,
28b, and 30b to an ovular cross-section shape as shown in FIGS. 2,
3 and 7. It is noted, that while each of the second portions 26b,
28b, and 30b have been described herein as ovular, the disclosure
is not so limited. Rather, the second portions 26b, 28b, and 30b
may be altered to have any appropriate cross-sectional shape
configured to prevent the moveable members 18, 20, and 22 from
twisting about and/or rotating about one another. For example, in
some embodiments, the second portions 26b, 28b, and 30b may include
the same cross-sectional shape as the first portions 26a, 28a, and
30a, but having a smaller diameter. That is, each of the first
portions 26a, 28a, and 30a and the second portions 26b, 28b, and
30b may have a circular cross-sectional shape. However, a diameter
of the each of the first portions 26a, 28a, and 30a may be larger
than a diameter of the a respective second portion 26b, 28b, and
30b.
[0033] Further, the second portions 26b, 28b, and 30b of the
support members 26, 28, and 30 may each be positioned along a
proximal portion, adjacent proximal ends 66, 68, and 70,
respectively, of the support members while first portions 26a, 28a,
and 30a of the support members 26, 28, and 30 are positioned along
a distal portion, adjacent distal ends 76, 78, and 80,
respectively, of the support member 26, 28, and 30, as shown in
FIGS. 2, 3, 5, and 7. However, the disclosure is not so limited.
Rather, second portions 26b, 28b, and 30b of the support members
26, 28, and 30 may be positioned at any location along the length
of support member 26, 28, and 30. For example, as shown in FIG. 8,
a central portion of each of the support member 26, 28, and 30, may
be flattened such that the second portions 26b, 28b, and 30b of the
support members 26, 28, and 30 may be positioned between distal and
proximal first portions 26a, 28a, and 30a of the support members as
shown in FIG. 8. Alternatively, the entire length of the support
members 26, 28, and 30, from a proximal-most end to a distal-most
end of the support members 26, 28, and 30 may be flattened (not
shown). Alternatively, in some examples, multiple portions of one
or more of the support members 26, 28, and 30, may be flattened
such that each support member includes two or more second portions.
Additionally, it is noted that the placement and/or number of
second portions of at least one of the support members 26, 28, and
30 may be different than the placement and/or number of second
portions of at least one other of the support members 26, 28, and
30
[0034] The support members 26, 28, and 30 may be disposed
circumferentially about the longitudinal axis of the outer sheath
12, as shown in FIGS. 1-5. The longitudinal axes of the support
members may be disposed at equal intervals circumferentially about
the longitudinal axis. It should be noted, however, that any other
suitable number of support members and spacing configurations may
alternatively be utilized. As shown in FIGS. 3-6, each of the
movable members 18, 20, and 22 may extend distally from a first,
proximal end thereof that is coupled to the drive member 16, extend
distally through a support member 26, 28, and 30, along the first
leg 18a, 20a, and 22a, form the preformed U-shaped bend 18b, 20b,
and 22b, and extend proximally through a different support member
26, 28, and 30 along the second leg 18c, 20c, and 22c. In this
configuration, the preformed U-shaped bend may confine or urge the
support members 26, 28, and 30 toward a low profile in the
contracted state.
[0035] The movable members 18, 20, and 22, and the support members
26, 28, and 30, may be heat treated simultaneously, and the
material for the movable members 18, 20, and 22 and the support
members 26, 28, and 30 may be selected such that the support
members 26, 28, and 30 will not melt during heat treatment of the
movable members 18, 20, and 22. While three support members 26, 28,
and 30 are shown, for example, in FIGS. 1, 2, and 4, one or more
additional support members may be used.
[0036] As shown in FIG. 6, proximal portions of the support members
26, 28, and 30 may extend through the lumen 14, and may be covered
by the outer sheath 12. For example, a length of about 10
millimeters of one or more of the support members 26, 28, and 30
may be covered by the outer sheath 12, leaving a length of about
9.5 millimeters exposed distal to the outer sheath 12. Distal
portions of the support members 26, 28, and 30 may extend distally
out of the lumen 14 and away from the distal end of the outer
sheath 12. The distal portions may be configured to move towards
and away from the longitudinal axis of the outer sheath 12. The
number of support members 26, 28, and 30 may be equal to the number
of movable members 18, 20, and 22. Alternatively, the number of
support members 26, 28, and 30 may be less than the movable members
18, 20, and 22.
[0037] Each of the three support members 26, 28, and 30 may be
coupled to the outer sheath 12 via an adhesive 13, such as an
ultraviolet light curable adhesive or cyanoacrylate. Additionally
or alternatively, the distal end of the outer sheath 12 may be
fixedly coupled to the proximal ends of the support members 26, 28,
and 30 by heat shrinking or by using a coupling tube glued at both
ends. The coupling may keep the proximal ends of the support
members 26, 28, and 30 stationary relative to the distal end of
outer sheath 12, while allowing the distal ends of the support
members 26, 28, and 30 to move relative to the distal end of the
outer sheath 12 and relative to one another.
[0038] The first leg 18a may extend distally from the drive member
16, and may enter a lumen at the proximal end of the support member
26. The first leg 18a may extend distally through the lumen of the
support member 26, and may exit the distal end of the support
member 26. There, the first leg 18a may transition into the bend
18b. The bend 18b may transition into the second leg 18c. The
second leg 18c may enter a lumen at the distal end of the second
support member 28. The second leg 18c may extend proximally through
a lumen of the second support member 28, and may exit the proximal
end of the support member 28.
[0039] The first leg 20a may extend distally from the drive member
16, and may enter the lumen at the proximal end of the second
support member 28. The first leg 20a may extend distally through
the support member 28, and may exit the distal end of the support
member 28. There, the first leg 20a may transition into the bend
20b. The bend 20b may transition into the second leg 20c. The
second leg 20c may enter a lumen at the distal end of the third
support member 30. The second leg 20c may extend proximally through
the third support member 30, and may exit the proximal end of the
third support member 30.
[0040] The first leg 22a may extend distally from the drive member
16, and may enter the lumen at the proximal end of the third
support member 30. The first leg 22a may extend distally through
the third support member 30, and may exit the distal end of the
third support member 30. There, the first leg 22a may transition
into the bend 22b. The bend 22b may transition into the second leg
22c. The second leg 22c may enter the lumen at the distal end of
the first support member 26. The second leg 22c may extend
proximally through the first support member 26, and may exit the
proximal end of the first support member 26.
[0041] One or more of the proximal or second ends of the second
legs 18c, 20c, and 22c may include a movable stop sized to abut or
engage a proximal end of a support member 26, 28, and 30 after
moving a distance 47 distally during movement of the retrieval
device toward the expanded state. The movable stop may be formed in
a number of different ways. An exemplary movable stop is shown in
FIGS. 4 and 6, and includes a coupler 46 in the form of a tube
including a lumen 48 configured to receive proximal ends of the
second legs 18c, 20c, and 22c. The second legs 18c, 20c, and 22c
may be attached to each other within the coupler 46 and attached to
the coupler 46. For example, each of the second legs 18c, 20c, and
22c may be attached to each other and the coupler 46 by adhesive,
melting, welding, crimping, friction fit, heat-shrinking the
coupler 46, and/or any other suitable form of attachment. Portions
of the first legs 18a, 20a, and 22a may extend along the side of
the coupler 46, and may contact the exterior surface of the coupler
46. The coupler 46 may space portions of the first legs 18a, 20a,
and 22a apart from the longitudinal axis of the outer sheath 12, to
help guide the first legs 18a, 20a, and 22a into the support
members 26, 28, and 30 (via first tubes 26a, 28a, and 30a,
respectively).
[0042] Alternatively, the movable stop could be formed by replacing
the two movable members 18 and 20 with a single moveable member
having a U-shaped bend replacing the proximal ends of the second
legs 18c and 20c. In this arrangement, the U-shaped bend could form
the movable stop of the movable members against the proximal end of
the support members 26, 28, and 30 during a first phase of the
expansion of the retrieval device 10. Further, the second leg 22c
could be coupled to the U-shaped bend to limit its travel.
Alternatively, proximal U-shaped or L-shaped hooks, or any other
type of obstruction (not shown) could be provided on one, two, or
all of the second legs 18c, 20c, and 22c to form the movable stop
for abutting or engaging the support members 26, 28, and 30 and
limiting movement of the second legs 18c, 20c, and 22c to the
distance 47 during the first phase of expansion of the retrieval
device 10.
[0043] The movable members 18, 20, and 22, and the support members
26, 28, and 30, may form an end effector 50. The end effector 50
may together form the basket or grasper portion 52. In FIGS. 3-6,
the grasper portion 52 is shown in the retracted and contracted
state. The grasper portion 52 may be moved into its retracted and
contracted state by moving the drive member 16 proximally relative
to the outer sheath 12, or moving the outer sheath 12 distally
relative to the drive member 16. Reference to support members 26,
28, 30 being moveable, refers to the relative movement of members
26, 28, 30 in relation to other elements of the retrieval device
10, and thus it is understood that the term "movable" includes the
support members being axially stationary during movement between
the contracted and expanded states, but movable radially in
relation to outer sheath 12 during movement between the contracted
and expanded states. In the retracted/contracted state, the bends
18b, 20b, and 22b may be at or adjacent to the distal ends of the
support members 26, 28, and 30. The longitudinal axes of the
support members 26, 28, and 30 may be substantially parallel, and
distal portions of each of the support members 26, 28, and 30 may
be in contact with the other support members. Portions of the first
legs 18a, 20a, and 22a and the second legs 18c, 20c, and 22c in the
lumens of respective support members 26, 28, and 30 may be
substantially parallel to one another. The support members 26, 28,
and 30, and/or the outer sheath 12 may help to resist bowing of the
movable members 18, 20, and 22 during movement of the device
between the expanded and contracted states.
[0044] In the retracted/contracted state, the distal end of the
coupler 46 may be spaced from the proximal ends of the support
members 26, 28, and 30 by a distance 47. The distance 47 may be
about 1 millimeter, although other distances may also be used. The
proximal end of the coupler 46 may be spaced from the distal end of
the sleeve 24 by a distance 49. The distance 49 may be about 16
millimeters, although other distances may also be used. In another
example, distance 49 may be about 11 millimeters. Other distances
49 may position sleeve 24 in a more proximal position relative to a
flexible ureteroscope channel where the ureteroscope scope does not
deflect. This positioning may prevent binding of sleeve 24 within a
curved portion of sheath 12. However, it is also contemplated that
sleeve 24 may include one or more flexible materials. The distances
47 and 49 may vary based on the procedure being performed with the
retrieval device 10.
[0045] In FIGS. 1 and 2, the retrieval device 10 is shown with the
grasper portion 52 in an extended and expanded state. In the
extended and expanded state, portions of the movable members 18,
20, and 22 may be exposed from the distal ends of the support
members 26, 28, and 30 and the outer sheath 12. Once exposed, one
or more of the movable members 18, 20, and 22 may move radially
outwardly from the longitudinal axis of the outer sheath 12 due to
a natural and/or applied radially outward biasing in one or more of
the movable members 18, 20, and 22. Radially outward movement of
one or more of the movable members 18, 20, and 22 may cause a
corresponding radially outward movement of the support members 26,
28, and 30.
[0046] Referring to FIG. 2, the exposed portions of the movable
members 18, 20, and 22 may form bridges 62, 64, and 66 between the
distal ends of the support members 26, 28, and 30. Each bridge may
extend distally from the distal end of a given support member 26,
28, 30, and may be received in the distal end of an adjacent
support member 26, 28, 30. The bridges 62, 64, and 66 may be formed
by distal portions of the first legs 18a, 20a, and 22a, the bends
18b, 20b, and 22b, and distal portions of the second legs 18c, 20c
and 22c.
[0047] Each bridge and its corresponding two support members may
form a side loop of the grasper portion 52. Three side loops 54,
56, and 58 are shown in FIG. 2. The bridges 62, 64, and 66 may form
a front loop 60 of the grasper portion 52 (a front loop 60 facing
distally). Materials may enter the grasper portion 52 through one
or more of the front loop 60 and the side loops 54, 56, and 58. By
adding additional movable members and support members, additional
side loops can be created.
[0048] Relative movement between drive member 16 and outer sheath
12 may cause grasper portion 52 to move to its extended and
expanded state due to a natural and/or applied radially outward
biasing in one or more of the movable members 18, 20, and 22.
Extension and expansion of the grasper portion 52 may occur in
phases. Starting from the retracted and contracted state shown in
FIG. 3, a first phase of the extension and expansion of the grasper
portion 52 may begin with movement of the drive member 16 distally
relative to the outer sheath 12 and the support members 26, 28, and
30. The relative movement of the drive member 16 may cause the
movable members 18, 20, and 22 and the coupler 46 to move distally
relative to the outer sheath 12. The movement of the drive member
16, movable members 18, 20, and 22, and coupler 46 may be
translational. For example, the drive member 16, first legs 18a,
20a, and 22a, bends 18b, 20b, and 22b, second legs 18c, 20c, and
22c, and coupler 46, may move distally relative to the outer sheath
12 and support members 26, 28, and 30 during the first phase.
Proximal portions of the first legs 18a, 20a, and 22a and second
legs 18c, 20c, and 22c may enter the lumens at the proximal end of
support members 26, 28, and 30. Distal portions of the first legs
18a, 20a, and 22a, bends 18b, 20b, and 22b, and second legs 18c,
20c, and 22c may emerge from, or extend further out from, the
distal ends of the support members 26, 28, and 30.
[0049] The coupler 46 forming the movable stop moves with the
movable members 18, 20, and 22 relative to the outer sheath 12 and
support members 26, 28, and 30. When the coupler 46 has traveled
the distance 47 relative to the outer sheath 12 and support members
26, 28, and 30, further distal movement of the coupler 46 may be
halted as the coupler 46 approaches the proximal ends of the
support members 26, 28, and 30. This prevents the second legs 18c,
20c, and 22c from further entering the lumens of second tubes 28b,
30b, and 26b. At the end of the first phase of extension and
expansion, the bends 18b, 20b, and 22b may each be spaced from
distal ends of the support members 26, 28, and 30 by the distance
47 because the U-shaped bends 18b, 20b, and 22b are located a fixed
distance from the coupler 46.
[0050] The presence of distance 47 between the support members 26,
28, and 30, and the coupler 46 facilitates the reciprocal movement
of retrieval device 10 between the contracted and expanded states.
That is, the presence of distance 47 reduces an initial amount of
force required to move retrieval device 10 from the contracted
state toward the expanded state. As described above, movable
members 18, 20, and 22 may include a preset U-shape bend 18b, 20b,
and 22b that serves to help clamp the distal end of the support
members 26, 28, and 30 in the contracted state. By extending the
movable members 18, 20, and 22 the distance 47, the clamping
resistance of the U-shaped bends 18b, 20b, and 22b on the distal
ends of the support members 26, 28, and 30 may be reduced.
Moreover, movement of the movable members 18, 20, and 22 away from
the distal end of the support members 26, 28, and 30 may provide a
greater moment arm to overcome the bias of the U-shaped bends 18b,
20b, and 22b when moving the retrieval device 10 toward the
expanded state.
[0051] The presence of distance 47 may also permit retrieval device
10 to form a first stage grasper by the portion of the movable
members 18, 20, and 22 extending distally of the support members
26, 28, and 30. This first stage grasper can capture smaller
fragments within only the portion of movable members 18, 20, and 22
extending distally from support members 26, 28, and 30 after
movement of the distance 47. The distal ends of movable members 18,
20, and 22 may more securely capture smaller fragments than support
members 26, 28, and 30 because they include a more distributed
contact array or wire web than the support members 26, 28, and 30.
It is noted that during the first phase movement of the movable
members 18, 20, and 22, the support members extend generally
parallel to one another. As understood, the word "generally" as
used herein means mainly, and if more specificity is required,
means a range of plus or minus eight percent of the relevant
value.
[0052] A second phase of the extension and expansion of the grasper
portion 52 may begin after distal movement of the coupler 46 has
been halted. During the second phase, further distal movement of
the drive member 16 relative to the outer sheath 12 and support
members 26, 28, and 30 may drive distal movement of the first legs
18a, 20a, and 22a relative to the outer sheath 12 and support
members 26, 28, and 30. During the second phase, the second legs
18c, 20c, and 22c may remain stationary relative to the support
members 26, 28, and 30. The first legs 18a, 20a, and 22a may be
increasingly exposed from the distal ends of the support members
26, 28, and 30, thereby increasing the lengths of the bridges 62,
64, and 66. Distal portions of the movable members 18, 20, and 22,
and the support members 26, 28, and 30, may expand radially
outwardly. The front loop 60 and the side loops 54, 56, and 58 may
also expand in size.
[0053] Extension and expansion in the second phase may continue
over the distance 49. Once the first legs 18a, 20a, and 22a have
traveled the distance 49, distal movement of the drive member 16
may halt. Distal movement of the drive member 16 may be halted, for
example, by a stop formed in the handle assembly shown in FIG.
1.
[0054] Moving the grasper portion 52 back to the retracted and
contracted state may be accomplished by moving the drive member 16
proximally relative to the outer sheath 12 and support members 26,
28, and 30. Movement from the extended and expanded state to the
retracted and contracted state may also occur in phases. A first
phase of the retraction and contraction of the grasper portion 52
may begin with the drive member 16 moving proximally relative to
the outer sheath 12. This may cause the first legs 18a, 20a, and
22a to move proximally relative to the outer sheath 12 and support
members 26, 28, and 30. Distal portions of the first legs 18a, 20a,
and 22a may enter the lumens at the distal ends of the support
members 26, 28, and 30. The second legs 18c, 20c, and 22c, and the
coupler 46 may remain stationary relative to the support members
26, 28, and 30. The lengths of the bridges 62, 64, and 66 may
decrease. The first legs 18a, 20a, and 22a, second legs 18c, 20c,
and 22c, and support members 26, 28, and 30 may move radially
inwardly. Thus, the front loop 60 and the side loops 54, 56, and 58
may decrease in size.
[0055] The first phase of the retraction and contraction of the
grasper portion 52 may take place over the distance 49. Once the
distance 49 has been covered, a second phase of the retraction and
contraction may take place with continued movement of the drive
member 16 proximally relative to the outer sheath 12 and the
support members 26, 28, and 30. The continued movement may cause
the movable members 18, 20, and 22 and the coupler 46 to move
distally relative to the outer sheath 12 and support members 26,
28, and 30. The movement of the drive member 16, movable members
18, 20, and 22, and coupler 46 may be translational. For example,
the drive member 16, first legs 18a, 20a, and 22a, bends 18b, 20b,
and 22b, second legs 18c, 20c, and 22c, and coupler 46, may move
proximally relative to the outer sheath 12 and the support members
26, 28, and 30 during the second phase. Distal portions of the
first legs 18a, 20a, and 22a may enter into, or move further past
the distal ends of the support members 26, 28, and 30, while the
second legs 18c, 20c, and 22c may enter into, or move further past,
the distal ends of the support members 26, 28, and 30. The lengths
of the bridges 62, 64, and 66 may decrease as the exposed lengths
of the movable members 18, 20, and 22 decrease. As the bridges 62,
64, and 66 shrink, distal portions of the movable members 18, 20,
and 22, and the support members 26, 28, and 30, may contract
radially inwardly toward the longitudinal axis of the outer sheath
22. The front loop 60 and side loops 54, 56, and 58 may also shrink
in size.
[0056] The coupler 46 may move with the movable members 18, 20, and
22 relative to the outer sheath 12 and support members 26, 28, and
30. When the coupler 46 has traveled the distance 47 relative to
the outer sheath 12 and support members 26, 28, and 30, further
proximal movement of the coupler 46 may be halted by operation of
the handle assembly 90, such as a stop formed in the handle
assembly 90 of FIG. 1. At the end of the second phase of retraction
and contraction, the state shown in FIGS. 3-6 is attained. As noted
above, in this contracted state, movable members 18, 20, and 22 may
include preset U-shape bends 18b, 20b, and 22b located adjacent the
distal ends of the support members 26, 28, and 30 that serve to
help clamp the distal end of the support members 26, 28, and 30 in
the contracted state.
[0057] Referring back to FIG. 1, the handle assembly 90 may be
disposed at the proximal end 86 of the retrieval device 10. Handle
assembly 90 may include the actuator 92 such as, e.g., a sliding
mechanism, rotating mechanism, pushing mechanism, or the like.
Actuator 92 may be coupled to outer sheath 12 and include internal
stops for limiting movement of the outer sheath 12 relative to the
movable members 18, 20, and 22. The drive member 16 may be fixed to
a proximal end of the handle assembly 90. It is understood that the
handle assembly may be formed in any conventional manner to control
the movement of movable members 18, 20, and 22 relative to the
outer sheath 12 and support members 26, 28, and 30 as described
above. As noted above, handle assembly 90 may include one or more
internal or external stops to limit movement of the movable members
18, 20, and 22.
[0058] The disclosed retrieval devices may be utilized in any
suitable application requiring the capture and removal of materials
from the body. Any aspect set forth in any example may be used with
any other example set forth herein. The devices may be used in any
suitable medical procedure, may be advanced through any suitable
body lumen and body cavity, and may be used to remove material from
any suitable body portion. For example, the devices described
herein may be used through any natural body lumen or tract,
including those accessed orally, vaginally, rectally, nasally,
urethrally, or through incisions in any suitable tissue.
[0059] The disclosed devices may be configured to capture fragments
having dimensions of about 3 French or smaller. In some examples,
the disclosed medical devices may be able to capture and release
smaller stones having diameters from 1 millimeter to 12
millimeters. In some examples, a user may want to reposition larger
stones from the lower calyx to the upper calyx of the kidney to be
broken with a laser before removing them through a small diameter
of the ureter. The stones may be removed in front of a scope, as
opposed to through scope channel to prevent damage to a scope
channel. When stones are removed, both an endoscope and the
retrieval device may be removed from the human body. In some
examples, a guide sheath for a ureteroscope may be used to guide
the ureteroscope and retrieval device back to a previous position
or to a new position to capture additional stones, and protect a
ureter wall during stone removal. While moving from the extended
and expanded state to the retracted and contracted state, retrieval
devices of the present disclosure may ligate larger stones and
capture smaller stones within the grasper portion 52.
[0060] It will be apparent to those skilled in the art that various
modifications and variations can be made in the disclosed systems
and processes without departing from the scope of the disclosure.
For example, the retrieval device disclosed could include more than
three support members, such as four or five support members, and an
equal number or less movable members. Other examples of the
disclosure will be apparent to those skilled in the art from
consideration of the specification and practice of the features
disclosed herein. It is intended that the specification and
examples be considered as exemplary only.
* * * * *